import { expect, it } from "bun:test";
import { mkdtemp, rm } from "node:fs/promises";
import { tmpdir } from "node:os";
import { join, resolve } from "node:path";
import { createServer } from "node:net";

const availablePort = () => new Promise<number>((done, reject) => {
  const server = createServer();
  server.once("error", reject);
  server.listen(0, "127.0.0.1", () => {
    const port = (server.address() as { port: number }).port;
    server.close((error) => error ? reject(error) : done(port));
  });
});

it("passes the isolated connection path to OpenCode before the Agent writes it", async () => {
  const root = await mkdtemp(join(tmpdir(), "query-launcher-test-"));
  try {
    const ports = await Promise.all([availablePort(), availablePort()]);
    // Execute the real launcher up to its first dependency. No OpenCode, Agent,
    // provider or business service starts; the dependency records its inputs.
    const script = `import { mock } from "bun:test";
      mock.module(${JSON.stringify(resolve("src/runtime/opencode2-server.ts"))}, () => ({ startOpencode2: async (options) => {
        console.log("LAUNCHER_ENV=" + JSON.stringify({ connection: options.env.TJWATER_AGENT_MCP_CONNECTION_PATH }));
        return { password: "TEST_ONLY", exited: Promise.resolve(0), close() {}, client: { server: { async info() { throw new Error("STOP_BEFORE_AGENT"); } } } };
      } }));
      await import(${JSON.stringify(resolve("scripts/start-isolated-integration.ts"))});`;
    const child = Bun.spawn([process.execPath, "-e", script], { cwd: process.cwd(),
      env: { ...process.env, INTEGRATION_DATA_DIR: root, INTEGRATION_AGENT_PORT: String(ports[0]), INTEGRATION_OPENCODE_PORT: String(ports[1]),
        TJWATER_AGENT_MCP_CONNECTION_PATH: "/unrelated/connection.json", AGENT_INTERNAL_TOKEN: "TEST_ONLY" }, stdout: "pipe", stderr: "pipe" });
    const [code, out, err] = await Promise.all([child.exited, new Response(child.stdout).text(), new Response(child.stderr).text()]);
    expect(code).toBe(1);
    expect(err).toContain("STOP_BEFORE_AGENT");
    const record = out.split("\n").find((line) => line.startsWith("LAUNCHER_ENV="));
    expect(record).toBeDefined();
    expect(JSON.parse(record!.slice("LAUNCHER_ENV=".length)).connection).toBe(join(root, "mcp-query", "connection.json"));
  } finally { await rm(root, { recursive: true, force: true }); }
});